JPS5976704A - Cutting insert combining control of chip - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to cutting tools for machining chip-forming materials. More particularly, the present invention relates to cutting inserts having particularly advantageous chip control geometries at relatively high feed rates.

Conventional tip control inserts require relatively high feed rates,
For example / θ- per rotation! ; exhibited performance problems when used at speeds of 0,020 inches or higher. These problems are caused by chip collisions caused by the cutting process, and collisions of the chip with seven or more portions of such prior art insert surfaces can result in premature wear and/or damage to the cutting insert material. or causing excessive friction and wear leading to breakage.

An example of prior art disclosing a chip control cutting insert with a geometry that impedes chip flow at higher feed rates is U.S. Pat.
No. 9 inventor Wirfalt's US Patent No. 3 Lamp J3 No. inventor Newmer's US Patent No. 3,3g/;
3'/-q Inventor Gotts' US Patent No. 3.
．． 2/3. This is No. RI/A.

It is therefore an object of the invention to use relatively high feed rates,
The present invention also provides a cutting tool that utilizes tip control geometries that are effective in overcoming the aforementioned problems associated with the prior art.

The present invention is embodied in a preferred form as an indexable cutting insert for processing chip-forming materials, the insert having improved chip control when used at relatively high feed rates. Lands extend around at least seven chip breaker or rake faces of the insert adjacent the insert cutting edges and cutting corners. Connected to the land is a seventh sloped surface, or chip control surface, extending downwardly from the peripheral land of the insert. The first bevel is broken at each cutting corner of the insert with a corner control plateau or surface to prevent damage caused by chip concentration behind the active cutting corner.

A first ramp or control surface is adjacent to the first ramp, and the viewing device has a first ramp or control surface at an angle of inclination that is less than the angle of inclination of the first ramp.
extending downward and inward from the slope of A third bevel connects the inner boundary of the corner control surface and the first bevel at each corner area of the insert.

The combination of bevel and control surface provides a relatively smooth chip flow at relatively high feed rates, thereby reducing cutting forces and friction.1 The combined shape of the various insert surface sections also provides a convex cross-section. Forming the tip with a higher feed rate allows for better control of the tip at relatively high feed rates.

Polygonal inserts designed in accordance with the present invention will exhibit long lifespans because their chip throughput more effectively resists cutting edge cratering and breakage.

These and other objects and features of the invention will become apparent from the detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings.

In order to better point out the advantages of the present invention, reference is first made to FIGS. 1-1, which illustrate various chip control geometries of the prior art. Prior art inserts having the chip control geometries shown in FIGS. The resulting chip is curled by the shoulder (number 102 in figure 1, number 204 in figure 1, number 404 in figure q) K and inserted in seven directions. Approximately 0.50 g tm (0.020 in.), which is adequate at relatively low feed rates of less than 7 n on the ribs, is adequate at relatively low feed rates. However, such shoulders become undesirable at higher feed rates, which result in thicker chips. Impacts with these shoulders create excessive friction (and therefore heat) and wear. Excessive heat causes chemical reactions between the workpiece tip and the insert material (such reactions also occur as built-up edges). Therefore, such a chip deflection layer wears out quickly under severe feed rate conditions.
As a result, the life of the insert will be reduced.

The prior art insert of FIG. 3 has a cutting edge 300 defined by the intersection of a flank surface 308 and a land 302, which is followed by an inclined surface 304 and a flat inner floor surface 306. Although the insert of FIG. 3 is effective at high feed rates, the insert may be placed in a negative orientation (i.e., The surface 306 is the cutting edge 300
Since the chip must be mounted at an angle (upwardly relative to the surface of the chip), a friction-generating surface is still present and disturbs the flow of the chips.

Another drawback to the use of tip control inserts designed according to FIGS. 2-2 at high feed rates arises from the use of internal cup-shaped recesses within the nose radius of the insert. During the material cutting process, the chip is forced into such a recess and at the same time tries to curl in qo degrees relative to the feed direction. This compound movement of the tip causes
The tip control geometry of the insert is subject to excessive forces caused by attempting to bend a relatively thick tip in several different directions at the same time. Such excessive force in the nose radius region makes the trailing edge of the nose radius susceptible to breakage at the effective cutting corners of the insert, thus shortening the life of the insert.

The cutting tools of the present invention, such as the inserts shown in FIGS. 3-7, have rake face geometries that overcome the aforementioned problems of prior art inserts used at relatively high feed rates. Referring to Figures 5-7, the cutting insert 10 has, for example, generally square top and bottom chip breaker surfaces which are generally perpendicular to the plane containing the chip breaker surfaces, i.e. They are connected by a side wall 7.

Two indexable cutting edges are formed by the intersection of the clearance surface 7 and the land area 1 extending around the chip breaker surface. As can be seen in FIG. 6, the angle a5 between the land 1 and the flank 7 is approximately 900 degrees.

The first slope, that is, the control surface 2, is the inner boundary K11 of land 1
g abutting, extending downward from the land at an angle a1 to the plane of the chip breaker face and between the cutting corners of the insert, the narrow portion 2 continues from the control Extends around the cutting corner.

A first slope, or control surface 3, is adjacent to the inner boundary of each slope 2a and is at an angle a2 to the plane of the chip breaker surface.
Extending downwards from a, the control surface 3 terminates in a floor surface 6 approximately parallel to the plane of the chip breaker surface. The insert 10 may be tightened at the cutting position tK using the central attachment point 11 in various known manners.

At each cutting corner of the insert, the bevel 2a is partially interrupted by a recessed plateau, namely a corner control surface 4, which in this embodiment is substantially parallel to the chip breaker surface. The inner boundary of each corner control surface 4 connects to the control surface 3 via a third slope 5 extending downwardly at an angle a3 to the plane of the chip breaker surface.

Land 10 width L1 is approximately 0.3g/Im (0,0/!
r inch) to O0gza9 Carp (0,03!r inch)
preferably in the range of about 0. II! r7 tm C0,
0/g inch) to O9ri 6 chicks C0,030 inch)
This provides sufficient corner size to resist deformation.

The ramps 2 and 2a extend downwardly at an angle a1 in the range of about 100 to 0, preferably in the range of about /So to -00 to provide a smooth, resistance-free chip flow path. The majority of chips resulting from relatively large cutting depths then range from about 3° to 0, preferably from about 3° to 0.
Proceed downward on the slope 3 extending downward at an angle a2 in the range of 0. Preferably, angle a1 is larger than angle a2. In such a configuration, the bevel 3 provides little or no resistance to chip flow, unlike the prior art flat garden insert of FIG. 3 discussed above. Even if crater wear were to occur on the bevel 3, the bevel 3 is spaced far enough inward of the insert cutting edge that no deleterious consequences affecting the life of the insert would occur.

Although the in-lengths of Figures S through 7 must be installed in a negative straight position, in the disclosed configuration
．． 2 and 3 smoothly with minimal resistance, allowing the chips to curl and break due to their inherent thickness and mechanical properties. With this, faces 1 and 2
The configurations of and 3 overcome the shoulder and floor friction problems encountered with prior art designs. This result is obtained because, after the chip has passed the land 1, it encounters a positively oriented slope 2.3 (inclined downwards from the plane in the feed direction).

The innermost boundary of slope 2a is at a distance H from the plane of land 1.
It is in 1. The distance MHI is approximately 0.10/m, (0.00
tI inch) to 0. (0,010 inches), preferably about 0.10/long<0.00'l (y
+ ) to O, KO KO RYU < o, oot inch). The innermost boundary of the slope 3 is at a distance H2 from the plane of the land 1. Distance H2/d approximately 0.30'
lt m (0,0/l y f ) to a maximum depth limited primarily by the required diameter of the mounting hole 11, preferably about. , 3o (0,01-inch) to θJ
The range is 0.020 inches. In order to overcome the above-mentioned problem of chip concentration near the nose radius of the cutting corner and the resulting high pressure, a pedestal or corner control surface 4 followed by a beveled surface 5 is provided on the inside of each insert cutting corner. It is located in The control surface 4 is at a depth H3 from the plane of the land 1. It is preferable that the depth H3 is approximately the same as the depth H1. 5-point control surface 4
Usable range of approximately 100 to 23 degrees from the inner boundary of
It preferably extends downwardly at an angle a3 in the range of approximately 73° to 200°. With this configuration, stresses are reduced in the area of the cutting corners. Another advantage of corner control surfaces, or tabletops, is the ability to provide excellent chip control at relatively shallow depths of cut. The control surface 4 deflects the chip and breaks it once the depth of cut has almost reached the control surface 4. Beyond this depth of cut, the chips flow freely due to the configuration of surface 2.3. Such free flow, together with the action of the corner control surfaces 4, creates a barrel-shaped or convex and somewhat brittle chip that facilitates breakage. The length dimension L2 (FIG. 3) is determined by the radius of curvature of the cut corner, and L2 is preferably in the range of about seven to three times such radius.

The diagram shows the deformed configuration of the land surface 1' intersecting the flank surface 7 at an obtuse angle a5' (i.e. the land 1' is inclined downward towards the cutting edge at an angle a4). . This variant is advantageous in applications requiring greater cutting edge strength, for example when machining hardened materials. angle a5
ranges from about deo0 to /,2o0, preferably about 900
It is preferable that the number be in the range of 1000 to 1000.

FIG. 9 shows yet another variant of the embodiment of FIGS. It is extending. The angle a6 is chosen to be smaller than the angle a1 of the first slope 2 (FIG. 7).

One corner control surface 4' is inserted due to the downward slope.
“Gives less resistance to chips that flow freely in the cutting corner areas.

A triangular insert designed in accordance with the principles of the present invention is shown in FIGS. 1O and 1/. -0.0 per revolution. ! rOg
For standard triangular inserts tested at relatively severe feed rates of II (0,0,20 inches) and above, the insert length 2° with conventional mounting holes 29 has lands 23 and Land 23 is preferably about Q, II left 7 wr
IICo, 0/g inch) and intersects the flank 22 at an angle of approximately 90°, thereby forming the cutting edge 21. The first slopes 24A, 24B are approximately 0, /l 111 (0) below the plane of the land 23 from the inner boundary of the land 23.
,004 inches) to the inner boundary located at approximately /S0
extends downward at an angle of The first slope 27 is approximately 0,'t below the plane of the land 23 from the inner boundary of the slope 24A.
It extends downwardly at an angle of about 70 degrees to the floor 28, which is positioned at a depth of OA (o, in.).

At each corner, the pedestal 25 intercepts the slope 24B to a depth of about 000-6 WIN (0,003 inches) below the plane of the land 23.

The third slope 26 extends downwardly at an angle of about -θ° to the platform 2.
5 and the slope 27.

The invention has been described with respect to preferred embodiments solely for purposes of illustration and without excluding variations that may be obvious to those skilled in the art. For example, the various control surfaces and ramps described above may be arcuate rather than planar, as long as the intersections of the various surfaces are tangentially connected in a manner that eliminates chip impact barriers.

The invention is to be limited only by the scope of the claims that follow.

[Brief explanation of drawings]

FIGS. 1-4 illustrate cross-sectional views of various prior art chip control geometries used in the chip breaker or rake face of known cutting inserts. FIG. 5 is a perspective view of an insert designed in accordance with the principles of the present invention. FIG. 6 is a sectional view taken along line A--A in FIG. FIG. 7 is a sectional view taken along the Cook line in FIG. 5. Figure 1 shows a sectional view of the first variant embodiment. FIG. 9 shows a sectional view of the first variant embodiment. FIG. 10 is a plan view of a modified cutting insert designed in accordance with the principles of the present invention. Figure 1 is a sectional view at //-1iH of Figure 7. 100.200,400 ...... Cutting blade,
102.204,404 ・・・・・・Shoulder, 3
08 ・・・・・・・・・Running surface, 302 ・・・
...... Land, 10... Cutting insert, 7... Side wall or flank,
1...Land area, 3...
...Control surface, 11...Central mounting hole, 4...Corner control surface, 5...
...Third slope, 2.2a...Slope, 1'...
・・Land surface, 4′・・・Corner control surface, 20・・・・・Insert, 23・・
...... Land, 24A, 24B...
...Seventh slope, 27...Second slope, 25...Plateau, 28...
··Floor,

Claims (1)

[Claims] /) A land surface extending inwardly from the cutting corner in a preliminary tool for cutting a chip-forming material having a cutting corner formed by the intersection of a chip breaker surface and one flank surface. a first control surface extending downwardly from the inner boundary of the land surface at a seventh angle relative to the plane of the chip breaker surface; and a corner control extending inwardly from the inner boundary of the first control surface. a first control surface extending downwardly from the inner boundary of the corner control surface at a first angle to the plane of the chip breaker face; and from the inner boundary of the first control surface to the plane of the chip breaker face; a third control surface extending downwardly at a third angle thereto; and a cutting tool having: a third control surface extending downwardly at a third angle; 2) the land surface further extends from the cutting corner and intersects with at least seven flank surfaces to define a cutting edge, and the first control surface further extends parallel to the cutting edge adjacent to the inner boundary of the land surface; , the third control surface further extends parallel to the cutting edge adjacent to the inner boundary of the seventh control surface, and the intersection of the seventh and third control surfaces is defined by the boundary of the first control surface at the cutting corner. 8. The cutting tool according to claim 7, wherein the cutting tool is obstructed. 3) Cutting tool according to claim 1, characterized in that the corner control surface extends substantially parallel to the plane of the chip breaker surface. 4. The cutting tool according to claim 3, wherein the reland surface extends substantially parallel to the plane of the chip breaker surface. S) Cutting tool according to claim 3, characterized in that the land surface intersects at least one flank surface at an obtuse angle. 6) The corner control surface extends downwardly from the boundary of the first control surface at an angle smaller than the first angle with respect to the plane of the chip breaker surface. Cutting tools. 7) consists of a polygonal body having opposing top and bottom surfaces lying on approximately parallel planes and polygonal sides formed by side surfaces approximately perpendicular to said planes and meeting at polygonal cutting corners. In the cutting insert, at least seven of the top and bottom surfaces include substantially flat lands intersecting on each side to define a peripheral cutting edge extending between the cutting corners; a substantially flat first slope extending downwardly at a first angle relative to the plane; and a generally flat first slope extending downwardly from an inner boundary of the first slope at a first angle relative to the plane. and a substantially flat third slope, each located at each cutting corner so as to block a portion of the first slope, and a third substantially flat slope, each connecting the inner boundary of the corresponding control surface to the first slope. A cutting insert characterized by having the following. g) Cutting insert according to claim 3, characterized in that the lands are substantially perpendicular to the sides. q) Cutting insert according to claim 3, characterized in that the control surface is substantially parallel to the plane. / land is 0.3g/tan (θ, 0/
! The cutting insert according to claim 9, wherein the cutting insert extends inward a distance of the order of 0-0.3/inch) to θ·gg9·tm (0-0.3/inch). //) The first slope is 0.0. /θ/
m5 (0,00'l y chi) to 0.234'
The cutting according to claim 9, characterized in that the cutting extends downward at a seventh angle of about 100 to -00 to an intersection with the first slope of about wn (0,010 inch). insert. lλ) The second slope is at least θ-30'lt IIIm C0-0/2 Iy +) below the plane containing the land.
The cutting insert according to claim 9, characterized in that the cutting insert extends downwardly at a first angle of about 75 degrees from a distance M-f''t'S0. are respectively o and os below the plane containing the land.
ozatnx+ (0-00, 2 inches) to 0. /270
The cutting insert according to claim 9, characterized in that the cutting insert intersects the first slope at a distance of the order of 0,0 (B inches). The cutting insert according to claim 1, wherein the cutting insert extends downward at an angle of about 100 to 25 degrees with respect to the parallel plane of the bottom surface. Q10 tan (0,0
The first sloped surface extends inwardly to a distance of the order of ./inch), and the first slope is below the plane containing the land, θ, /! ;,2tm (0,00
6 inches) extending downwardly at a first angle of about 150 degrees to an intersection with a first slope of about 0.6 inches below the plane containing the land. The control surfaces extend downwardly at a feed angle of approximately 7° to a distance of approximately 0.06 m (0.076 in.), and the control surfaces are respectively 0.07 A and 2 mm (0.00 mm) below the plane containing the land.
3 inches), and the third slopes each extend downwardly at an angle of about 100 with respect to a plane parallel to the top and bottom surfaces. Cutting inserts as described in Section 6 of the scope.